Process of uniting parts of artificial resin and article made thereby



PROCESS OF' UNITEING PARTS OF' ARTIFICIAL RESIN AND ARTICLE MADE Feb. 18, 1930. v J.AK WIRTII THERE-:BY

Filed Jan'. 3, 1927 ,5 often has a serious effect.

Patented Feb. 18, 1930 UNITED STA 'JOHANN um. wm'rn, or BERLIN-ALTGLIENIGKE, annum PROCESS OF UNITINGYARTS OF ARTIFICIAL RESIN AND ARTICLE MADE THEREBY application alea'nnuary a, 1927, serial' No.

In constructive work with artificial resins i. e., with hardened phenol-formaldehyde artificial resins the quite considerable shrinkage of material during the hardening process This shrinkage which is largely due to the separation of water and other volatile constituents during the condensation process may also, in connecting or joining separate artificial resin` 10' plates by means of un-hardened mixtures of phenol-formaldehyde condensation products and fillers, cause breakage of the joint in consequence of the expansion or contraction of the material. Such circumstances arise generally when the abutting edges or surfaces to be joined or connected are smooth. When the joint isonly a few millimetres in width the' shrinkage during hardening of the inserted artificial resin mixture used is sufficient to losen the joint more or less.

It has now been ascertained that this disadr vantageous property of the material can be completely neutralized if the artificial resin ,surfaces orpedges to be connected are homogeneously welded together in a manner such that they interlock. By homogeneous weldmg is meantthe connection of the hardened artificial resin parts by means of similar but gagement is meant, in the present instance,l

not hardened artificial resin products and subsequently hardening. By interlocking en# joint.

In the accompanying drawing the process according to the invention is illustrated in: Figure 1 diagrammatically, Figure 2 on a frame with a curved bottom, Figure 3 on a container or the like being provided with iron reinforcements, and Figure 4 on an iron channel lined with. artificial resin plates;

158,809, and in Germany February 2, 1928.

Fi ure 4* is a section according to the line a: y in ig. 4.

According to Fig. 1 a and b are artificial resin plates to be connected. The edges to be connected are provided with recesses c. The joint between a and I) is filled with a plastic phenol-formaldehyde artificial resin mlxture. After the hardening operation this jointing material d presents a considerabl narrowed portion resulting from the shrin age of the' material. -If the recesses e had not been provided the j ointing material al would have loosened from the edges of the artificial resin plates orthere would have been considerable stress in the material in the joint which in course of time would have led to loosening of the joint.

As a second example, take an artificial resin frame with a curved bottom. In Fig. 2, a denotes the frame consisting of artificial resin. The lower edge of this frame is provided with indentations or teeth c. The indentations are suitably of dovetail form or may be of another undercut form. The undercut form is, however, not essential. Now, the bottom b is moulded of a suitable unhardened, i. e. plastic, artificial resin mixture on the rame'in such manner that the soft material forms a ood connection with the teeth. After the ardening operation the connection between the frame and bottom is as intimate as if the whole container were in one piece.

Circumstances may often arise where iron reinforcements are necessary for supportlng the parts. Quite often shaped iron reinforcements are sufiicient. As a third example, Fig. 3 shows such an arrangement. The construction is clear from the drawing in which a and b are curved artificial resin plates which are screwed to the an le irons e by means of inserted screws f. he plates are formed on their 'edges with grooves or passages c which serve to hold the inserted plastic jolntin material d durin the hardening recess.

n this manner, tu s,'troughs or ot er apparatus and devices may be produced from artificial resin plates and shaped iron reinforcements.

Sometimes the shaped iron stifeners are insucient and the artificialv resin plates must be su ported by solid metal supports. The fourt example illustrates this arrangement in Figs. 4 and 4 showing an iron channel which is lined on its inner surface with artificial resin plates. In both figures .e denotes the iron channel, a and b the inserted correspondingly shaped artificial resin plates which are screwed by screws f on the iron support. The abutting joints of the plates are formed with indentations, holes .or other uneven portions in order to hold the jointing material d consisting of artificial resin during the hardening operation. The bolts with'which the artificial resin plates are fastened to the iron base need not be of iron or other metal, but may be of artificial resin itself.

By the method described not only can artificial resin parts be connected with one another, but arts of other products can be connected wit artificial resins.

I claim:

1. A method of connecting artificial resin plates or other artificial resin parts with one another or with parts of other Y iaterials for the purpose of forming containers, vessels or other hollow bodies, apparatus or parte of the same, consisting in providing the edges or surfaces to be connected with slots, recesses or indentations or other analogous forms, effecting the homogeneous connection or jointing with unhardened artificial resin masses, and hardening these masses 2. A hollow body made of hardened artificial resin under conditions in which excessive shrinkage of the walls of said body occur in the process of hardening the same,

comprising a wall of artificial resin having the connected edges thereof formed'so as to adapt them to interlock, and a layer of artificial resin in the joint between said` interlocking edges homgeneously welded to said edge to unite them.

' 3. A hollow body made of hardened artificial resin under conditions in which excessive shrinkage of the walls of said body occur in the process-of hardening the same comprisin plates of artificial resin, the joints of which are homogeneously welded together with artificial resin masses in interlocking engagement.

4. A hollow body made of hardened artificial resin under conditions in which excessive shrinkage of the walls of said body occur in the process of hardening the samecom l prising a lmetal frame, and artificial resin plates secured to said frame, the joints of said plates being homogeneously Welded tolglether in interlocking engagement with articial resin masses.

' 5. A hollow body made of hardened artificial resin under conditions in which excessive shrinkage of the Walls of said body occur in the process of hardening the same comprising a metal support having attache yun 

